hey y'all,
here's the skinny on what I've been doing, and the results:

ecasound -r -b:1024 -i:bass.wav -o:bass1.wav -t:287.27

this command was intended to clip the first 287.27 seconds of the 'bass.wav'
file and paste it to 'bass1.wav' Now, I then recorded a "punch-in" track,
called 'bass2.wav' under ecasound-iam, starting at position 280 seconds. I
wanted to merge 'bass1.wav' and 'bass2.wav' to paste the "punch-in" to the
original track by employing the following command:

Now, the "punch-in" worked, although when the punch-in occurred at position
287.27 seconds, the result was a layered *.wav file: one layer was the
actual bass track, and over that was this awful garbage-noise, like a
low-frequency saw-wave.